First Online: 05 October 2016Received: 25 April 2016Revised: 25 August 2016Accepted: 30 August 2016

AbstractAlliance formation is a critical dimension of social intelligence in political, social and biological systems. As some allies may provide greater -leverage- than others during social conflict, the cognitive architecture that supports alliance formation in humans may be shaped by recent experience, for example in light of the outcomes of violent or non-violent forms intrasexual competition. Here we used experimental priming techniques to explore this issue. Consistent with our predictions, while men’s preferences for dominant allies strengthened following losses compared to victories in violent intrasexual contests, women’s preferences for dominant allies weakened following losses compared to victories in violent intrasexual contests. Our findings suggest that while men may prefer dominant i.e. masculine allies following losses in violent confrontation in order to facilitate successful resource competition, women may -tend and befriend- following this scenario and seek support from prosocial i.e. feminine allies and-or avoid the potential costs of dominant allies as long-term social partners. Moreover, they demonstrate facultative responses to signals related to dominance in allies, which may shape sex differences in sociality in light of recent experience and suggest that intrasexual selection has shaped social intelligence in humans.

Significance statementAlthough alliance formation is an important facet of social intelligence in political and biological systems, we know relatively little about the cognitive processes involved in social preferences for allies. As recent experience may alter the leverage provided by different social partners, here we tested whether preferences for facial cues to dominance-prosociality masculinity-femininity alter in light of recent experience of violent and economic contests for status. Our findings demonstrate sex-specific responses to these facial cues. While men’s preferences for facial cues related to dominance in allies strengthen following losses compared to wins in violent contests, women’s preferences for facial cues related to dominance in allies weaken following losses compared to wins in violent contests. These findings suggest that intrasexual selection, in part, has shaped the evolution of social intelligence in humans as revealed in flexibility in social preferences for allies.